Lobed balloons are used in high altitude ballooning. The shape of the lobed balloon has a relatively high curvature that allows for larger diameter balloons using relatively thin material for the balloon material. In at least some examples, payloads including instruments, communications equipment and the like are coupled with or suspended from the lobed balloon. The payloads are configured to conduct operations (e.g., observation, communication and the like) at the high altitudes lobed balloons reach, for instance an altitude of 20 miles.
Examples of lobed balloons are constructed with a lightweight material that is provided in diamond shaped panels of material (a gore pattern) that extend from top end to a bottom end and taper from near a midpoint toward the top and bottom ends. The diamond shaped panels are bonded to one another along their respective longitudinal edges to form the balloon. The balloon accordingly has a plurality of longitudinal seams extending from the top to the bottom of the balloon (one seam for each of the diamond shaped panels). The wider midpoint of each of the diamond shaped panels provides the outwardly curving shape of the balloon with respect to the narrower top and bottom ends. Optionally, a balloon is constructed with an upper and a lower panel coupled together along an edge.
In other examples of balloons a nested inner balloon, a ballonet, is provided within a larger balloon (e.g., a balloon within a balloon). The ballonet is coupled at an end of the larger balloon, for instance the bottom end of the larger balloon, and has a roughly spherical shape that fills at least a portion of the larger balloon. The ballonet (inner balloon) is inflated within the larger balloon. Inflation and deflation of the ballonet with atmospheric air provides ballast to the larger balloon by minimizing the remaining volume of the larger balloon dedicated to a lighter than air gas that provides buoyancy.